Packages and methods for storing and transporting perishable foods

ABSTRACT

Provided is a unitized packaging system and individual packaging elements for storing and transporting food in a controlled atmosphere. Also provided are the methods of storing and transporting food in a controlled atmosphere.

FIELD OF THE DISCLOSURE

Disclosed herein are controlled atmosphere packages for foods. Particularly, the disclosure relates to a unitized packaging system for storing and transporting food while maintaining an integrated controlled atmosphere throughout the system. In one embodiment, integration of the controlled atmosphere throughout the individual packaging elements of the unitized packaging system comprises a means for gaseous communication in each individual packaging system so as to permit gas flow throughout the system. In another embodiment, the unitized packaging system is composed of oxygen impermeable material with minimal heat transference. Methods of using such unitized packaging system are also disclosed.

STATE OF THE ART

Various types of packaging systems are employed for storage and transportation of food. Especially, certain types of food such as meats, seafood, fruits, and vegetables are placed into containers to preserve them for as long as possible prior to presenting them at a market where they are purchased. Maximizing the time in which these foods remain preserved in the containers increases the profitability of all entities in the chain of distribution by minimizing the spoilage.

The gaseous environment in which the foods are preserved is one of the critical factors in the preservation process. Another critical factor is maintaining an adequate temperature within the container in which the food is stored. By providing an appropriate controlled atmosphere surrounding the food and by maintaining an adequate temperature, the food can be stored and transported in an acceptable condition for the consumers. Typically, controlled atmosphere can be provided by decreasing the oxygen content and increasing content of other gases such as carbon dioxide, nitrogen, and the like.

Styrofoam™ and other normally sealed packages are generally not vented for gas exchange, as they are constructed from materials that are typically thermally insulative and are designed to maintain the temperature of the perishable product within the package with minimal temperature increases. Thermal insulation infers that there is little or no exposure to atmospheric conditions outside the package. This complicates matters significantly if the other objective is to facilitate gas exchange throughout the unitized system of individual packages.

Therefore, it is desirable to have a unitized packaging system that allows for gaseous communication throughout the system in a controlled atmosphere environment while preserving the thermal properties of the system as well.

SUMMARY

The present disclosure provides a unitized packaging system that provides a modified or controlled atmosphere for free movement of gases across the packaging system. In one embodiment, the free movement of gases allows modification of gaseous components within the unitized system such as removal of oxygen. In yet another embodiment, the use of a thermally insulative material provides adequate temperature control as well.

By treating a standard sealed package lid, walls, or bottom with machined, molded, stamped, or formed external channels and with perforations or holes in these channels through individual packaging element, vent paths are created for free movement of gases to travel along these channels and through the walls of the sealed package to the product within. With these individual packaging elements stacked and tightly unitized on a pallet, see, for example, FIG. 8, these channels provide a clear route to transfer gases during the application of the modified or controlled atmosphere environment to all individual packaging elements including the innermost in the pallet stack. The unitized packaging system or the container that stores these individual packaging elements, can also be manufactured to include side walls, top portion and bottom portion with no perforations or holes so as to enclose the system. Alternatively, the perforations or holes in the side walls, top portion and bottom portion can be plugged with a suitable material compatible with the packaging.

The unitized packaging system or the container that stores the individual packaging elements, comprises a material that is impermeable to gas, whereas the individual packaging element comprises a material that is either permeable or impermeable to gas. In one embodiment, the individual packaging element comprises a material that is impermeable to gas. In one embodiment, several unitized packaging systems can be stored in one container. The container comprises a material that is impermeable to gas. In one embodiment, the container is a plastic bag that can be sealed.

In one embodiment, the atmosphere within the unitized packaging system and/or element is controlled internally or externally in the manner of U.S. Pat. No. 8,187,653, which is incorporated by reference in its entirety. In some embodiments, the atmosphere within the unitized packaging system and/or element is controlled in the manner described in US Patent Application Publication Nos. 2011/0151070 and 2011/0151084, and International Application WO2011/053676. In some embodiments, the atmosphere within the unitized packaging system and/or element is controlled in the manner described in U.S. patent application Ser. No. 13/______, entitled “Systems and methods for maintaining foods” (Attorney Docket 072801-1252), U.S. patent application Ser. No. 13/______, entitled “Systems and methods for maintaining red meat” (Attorney Docket 072801-1301), and U.S. patent application Ser. No. 13/______, entitled “Systems and methods for storing and transporting perishable foods” (Attorney Docket 072801-1400), all filed on even date. All of which are incorporated by reference in their entirety. In another embodiment, the atmosphere within the unitized packaging system and/or element is controlled externally such that multiple unitized packaging system and/or elements are controlled by a single device such as fuel cell that will convert oxygen recovered from any of the packaging elements to water.

Alternatively, oxygen can be removed from the atmosphere internal to the unitized packaging element by any system suitable for such use including pressure swing, electrochemical devices, nitrogen membranes that filter oxygen out or other similar means, catalysts, adsorbers, absorbers, etc. that are known in the art. Such an embodiment is particularly useful when the oxygen removal system is used outside of a single or multiple unitized packaging element(s) where the atmosphere internal to each unitized packaging element(s) is in gaseous communication with the oxygen removing system.

After the treated packages have arrived at the destination, and have been removed from the modified or controlled atmosphere and before the packages have left the temperature controlled atmosphere environment, standard packaging tape can be applied to the channels covering the holes to minimize thermal losses. These packages can then be released to the traditional distribution chain with the same protections against thermal shocks as a standard sealed package of Styrofoam™ or other materials of construction.

In one aspect, this disclosure provides a unitized packaging system for storing and/or transporting food under controlled temperature and atmosphere conditions which system comprises:

-   -   two or more individual sealable packaging elements;     -   an oxygen controlling means for controlling the oxygen content         within the package system; and     -   optionally a means for maintaining ambient pressure within the         package system;     -   wherein each of the individual packaging elements is in gaseous         communication with at least another individual packaging element         and with said oxygen controlling means;         -   wherein said elements comprise a thermally insulative and             gas impermeable material; further wherein said elements are             stackable with each other.

In one aspect, this disclosure provides a unitized packaging system for storing and transporting food in a controlled atmosphere comprising:

-   -   one or more individual packaging element(s) comprising:         -   a bottom portion;         -   side walls; and         -   a closable top portion; and         -   a means for gaseous communication with another individual             packaging element and/or with the gaseous environment of the             unitized packaging system;             -   wherein said element(s) comprises a thermally insulative                 material;     -   an oxygen controlling means for controlling oxygen content of         the packaging system; and     -   optionally a means for maintaining ambient pressure within the         packaging system.

In one aspect, this disclosure provides an individual sealable packaging element comprising a sealable opening, a means for gaseous communication with at least another individual packaging element when the packaging element is sealed; and a thermally insulative material, wherein said elements are stackable with each other. In some embodiments, the sealable opening comprises a closable top portion of the packaging element. In some embodiments, the sealable opening comprises a sealable opening on a side wall of the packaging element.

In one aspect, this disclosure provides an individual packaging element suitable for use in a unitized packaging system for storing and transporting food in a controlled atmosphere comprising:

-   -   a bottom portion;     -   side walls;     -   a closable top portion; and     -   a means for gaseous communication with another individual         packaging element and/or with the gaseous environment of the         unitized packaging system, which system comprises an oxygen         controlling means for controlling oxygen content of the package         system, and optionally a means for maintaining ambient pressure         within the package system;         -   wherein said element comprises a thermally insulative             material

In one aspect, this disclosure provides a method for storing and transporting food in a controlled atmosphere in a unitized packaging system comprising a plurality of individual packaging elements comprising:

-   -   a) placing food in an individual packaging element, wherein said         element comprises:         -   a bottom element;         -   side walls;         -   a closable top element; and         -   a means for gaseous communication with another individual             packaging element and/or with the gaseous environment of the             unitized packaging system;             -   wherein said element comprises a thermally insulative                 material;     -   b) stacking individual packaging elements, wherein a second         individual packaging element is stacked on a first individual         packaging element;     -   c) placing the individual packaging elements in a unitized         packaging system;     -   d) controlling the oxygen content of the unitized packaging         system;     -   e) closing the unitized packaging system so as to keep food in a         controlled atmosphere; and     -   f) optionally maintaining ambient pressure within the unitized         packaging system using a means for maintaining pressure.

In one preferred embodiment, the packaging element comprises Styrofoam® as it possesses both thermal stability and adequate oxygen impermeability as well as being light weight.

In another embodiment, the means for gaseous communication comprises perforations, channels, grooves, holes, or the like.

BRIEF DESCRIPTION OF THE DRAWINGS

The figures of the accompanying drawings describe provided embodiments by way of illustration only:

FIG. 1 shows a perspective view of an individual packaging element with modified closable top element (lid) with perforations (gas channels and vent holes).

FIG. 2 shows a perspective view of the underside of a modified closable top element (lid) with raised reinforced sections to add structural strength in the perforations area.

FIG. 3 shows a top view of an individual packaging element with modified closable top element (lid) with perforations (channels and vent holes).

FIG. 4 shows a top view of an individual packaging element without modified closable top element (lid) with perforations.

FIG. 5A shows a top view of the modified lid of the individual packaging element;

FIG. 5B shows a bottom view of the box of the individual packaging element.

FIG. 6 shows a front view of an individual packaging element having locking mechanisms on the sides of the element wherein two sides of the bottom have an indentation having a depth of Y′ and the same sides on the top of the element protrude with a height of X′, wherein the height X′ of the protrusion is greater than the depth Y′ of the indentation.

FIG. 7 shows a front view of two individual packaging elements showing in FIG. 6 stacked together wherein the protruding sides of the top portion of the first packaging element is interlocked with the indentations of the bottom of the second packaging element stacked on top of the first packaging element. A gap is formed between the two packaging elements as the height X′ of the protrusions is greater than the depth Y′ of the indentations.

FIG. 8 shows a front view of a plurality of individual packaging elements stacked and tightly unitized on a thermally insulative pallet.

Some or all of the figures are schematic representations for exemplification; hence, they do not necessarily depict the actual relative sizes or locations of the elements shown. The figures are presented for the purpose of illustrating one or more embodiments with the explicit understanding that they will not be used to limit the scope or the meaning of the claims that follow below.

DETAILED DESCRIPTION

Before the compositions and methods are described, it is to be understood that the invention is not limited to the particular methodologies, protocols, and devices described, as these may vary. It is also to be understood that the terminology used herein is intended to describe particular embodiments of the present invention, and is in no way intended to limit the scope of the present invention as set forth in the appended claims.

Unless defined otherwise, all technical and scientific terms used herein have the same meanings as commonly understood by one of ordinary skill in the art to which this invention belongs. Although any methods and materials similar or equivalent to those described herein can be used in the practice or testing of the present invention, the preferred methods, devices, and materials are now described. All technical and patent publications cited herein are incorporated herein by reference in their entirety. Nothing herein is to be construed as an admission that the invention is not entitled to antedate such disclosure by virtue of prior invention.

When a numerical designation is preceded by the term “about”, it varies by (+) or (−) 10%, 5% or 1%. When “about” is used before an amount, for example, in mg, it indicates that the weight value may vary (+) or (−) 10%, 5% or 1%.

DEFINITIONS

In accordance with the present invention and as used herein, the following terms are defined with the following meanings, unless explicitly stated otherwise.

As used in the specification and claims, the singular form “a”, “an” and “the” include plural references unless the context clearly dictates otherwise. For example, the term “a fuel cell” includes a plurality of fuel cells, including mixtures thereof.

As used herein, the term “comprising” is intended to mean that the compositions and methods include the recited elements, but not excluding others. “Consisting essentially of” when used to define compositions and methods, shall mean excluding other elements of any essential significance to the combination. For example, a composition consisting essentially of the elements as defined herein would not exclude other elements that do not materially affect the basic and novel characteristic(s) of the claimed invention. “Consisting of” shall mean excluding more than trace amount of other ingredients and substantial method steps recited. Embodiments defined by each of these transition terms are within the scope of this invention.

The term “sealable” when used to define an individual packaging element means that the packaging element comprises a sealable opening where foods can be placed into or taken out of the packaging element when the sealable opening is sealed and that the packaging element does not have any opening except the means for gaseous communication when the sealable opening is sealed. The means for gaseous communication can further be sealed.

As used herein, the term “unitized packaging system” refers to a stabilized (for example, strapped or stretch-net wrapped), tightly block stacked unit of packages, such as bulk or retail packages. In one embodiment, the unitized packaging system is an outer container storing the individual packaging elements. In one embodiment, the unitized packaging system comprises a container within a container, wherein the inside container is the individual packaging element. In one embodiment, the outer container can be configured to assist in temperature control and/or to assist in limiting gas permeability.

As used herein, the term “bottom portion” refers to a base of an individual packaging element and the term “side walls” refer to the walls extending upwardly from the base. The side walls and the bottom portion define a cavity in which the contents are disposed. An example is illustrated in FIG. 4, with a bottom portion 400 and side walls 410. The term “top portion” refers to a portion that covers this cavity. In one embodiment, the top portion is a closable lid.

Unitized Packaging System

In one aspect, this disclosure provides a unitized packaging system for storing and/or transporting food under controlled temperature and atmosphere conditions which system comprises:

-   -   two or more individual sealable packaging elements;     -   an oxygen controlling means for controlling the oxygen content         within the package system; and     -   optionally a means for maintaining ambient pressure within the         package system;     -   wherein each of the individual packaging elements is in gaseous         communication with at least another individual packaging element         and with said oxygen controlling means;         -   wherein said elements comprise a thermally insulative and             gas impermeable material; further wherein said elements are             stackable with each other.

In one aspect, this disclosure provides a unitized packaging system for storing and transporting food in a controlled atmosphere comprising:

-   -   two or more individual packaging elements comprising:         -   a bottom portion;         -   side walls; and         -   a closable top portion; and         -   a means for gaseous communication with another individual             packaging element and/or with the gaseous environment of the             unitized packaging system;             -   wherein said elements comprise a thermally insulative                 material;     -   an oxygen controlling means for controlling oxygen content of         the packaging system; and     -   optionally a means for maintaining ambient pressure within the         packaging system.

In one embodiment, the closable top portion is detachably connected to the side walls. In another embodiment, the thermally insulative material comprises a polymer. In a further embodiment, the polymer is selected from the group consisting of polystyrene, polyester, polyurethane, polyethylene and polypropylene. In another embodiment, the individual packaging element comprises the thermally insulative material that is impermeable to gas. In another embodiment, the thermally insulative material comprises a polystyrene foam, such as Styrofoam™, or other extruded polystyrene foam. In another embodiment, the thermally insulative material comprises bio-based resins or plastics, for example, corn- or soy-based thermoset plastics or foam, and soy-based polyurethane. In one embodiment, the material comprises a reinforcing agent, such as pyrophyllite (e.g., PYRAX®), wollastonite (e.g., VANSIL®), calcium inosilicate mineral (CaSiO₃), air floated hard and soft clays, Hyperform® HPR-803i, talc, latex emulsion, etc., that are known in the art.

In another embodiment, the means for gaseous communication comprises perforations, channels, grooves, holes, or the like.

In one embodiment, the means for maintaining ambient pressure comprises the packaging system comprising a flexible, collapsible or expandable material which does not puncture when collapsing or expanding, and is able to accommodate for pressure change inside the packaging system. In another embodiment, the means for maintaining ambient pressure comprises a gas source, such as an inert gas source, to introduce additional gas to the packaging system when the internal pressure is below ambient pressure.

In one aspect, this disclosure provides an individual sealable packaging element comprising a sealable opening, a means for gaseous communication with at least another individual packaging element when the packaging element is sealed; and a thermally insulative material, wherein said elements are stackable with each other. In some embodiments, the sealable opening comprises a closable top portion of the packaging element. In some embodiments, the sealable opening comprises a sealable opening on a side wall of the packaging element.

In one aspect, this disclosure provides an individual packaging element suitable for use in a unitized packaging system for storing and transporting food in a controlled atmosphere comprising:

-   -   a bottom portion;     -   side walls;     -   a closable top portion; and     -   a means for gaseous communication with another individual         packaging element and/or with the gaseous environment of the         unitized packaging system, which packaging system comprises a         means for controlling oxygen content of the packaging system,         and optionally a means for maintaining ambient pressure within         the packaging system;     -   wherein said element comprises a thermally insulative material.

In one embodiment, the means for gaseous communication are perforations, grooves, or holes. In another embodiment, the perforations are parallel or aligned so as to allow the transfer of gases, providing a uniform environment through multiple packaging elements. A fan or multiple fuel cells can be used at different locations to provide circulations of gases creating a uniform environment.

With reference to FIG. 1, in one embodiment, this disclosure provides a Styrofoam™ packaging element (box) 100 and modified lid 110 with gas channels 120 and vent holes 130. The area of the gas channels on the lid is recessed only to be deep enough to allow gaseous communication so that the vent holes are not covered or blocked. FIG. 3 shows a top view of the modified lid 110 with gas channels 120 and vent holes 130. The sizes of the vent holes are preferably in a size that allows sufficient gaseous communication while minimizing thermo exchange between the internal atmosphere of the individual packaging element and the atmosphere of the packaging system and not significantly affect the strength of the packaging elements.

With reference to FIG. 2, in one embodiment, this disclosure provides a Styrofoam™ box 100 and modified lid 110 with gas channels and vent holes. The underside of the modified lid has raised reinforced sections 140 to add structural strength to the gas channel area (not shown).

With reference to FIGS. 5A and 5B, in one embodiment, this disclosure provides a Styrofoam™ box with modified lid with gas channels and vent holes. FIG. 5A shows a top view of a modified lid 110 with gas channels 120 and vent holes 130. FIG. 5B shows a bottom view of the box 100 with gas channels 150. The area of gas channels on the lid as well as on the bottom is recessed only to be deep enough to allow gaseous communication so that the vent holes are not covered or blocked. The recessed channel is about 0.1 to about 1 inch deep. In one embodiment, it is about 0.2 to about 0.8 inches deep. In another embodiment, it is about 0.4 to about 0.6 inches deep. In one embodiment, it is about 0.125 inches deep. In one embodiment, the recessed channel is about 18 millimeter (mm) to about 20 mm wide. In one embodiment, the recessed channel is about 19 mm wide. In some embodiments, the holes are about 20 mm to about 30 mm long and about 10 mm to about 15 mm wide, for example, about 25 mm long and about 13 mm wide, and are within the recessed channels.

Although the recessed area having the perforations, channels, grooves, or holes is illustrated in the figures in a cross configuration on the lid, it is to be understood that the specific design of the recessed area is not limited to the cross configuration and that other configurations are encompassed within the scope of the invention.

The size of the packaging element is not critical and packages of most any size can be used provided that they can be unitized in combination with each other. In one embodiment, the individual packaging element has a length of up to about 3 m, a width of up to about 3 m, and a height of up to about 3 m. In one embodiment, the individual packaging element is sized to fit a pallet which can be a standard pallet or a customized pallet.

With reference to FIG. 8, in one embodiment, this disclosure provides a unitized packaging system comprising a plurality of individual packaging elements 800 stacked together and tightly unitized on a thermally insulative pallet 810. On top of the unitized packaging elements is a means for controlling oxygen content 820. The packaging system comprises a gaseous environment 830. The top lid of each individual packaging element comprises a recessed area having the means for gaseous communication, such as perforations, channels, grooves, holes, etc. The recessed area allows a gap between one packaging element and the packaging element stacked on its top so that gas can enter into or come out of the packaging element through the perforations, channels, grooves, or holes and the gap. In some embodiments, the perforations, channels, grooves, or holes may be present on the side walls, and/or bottom of the packaging element. In some embodiments, the perforations, channels, grooves, or holes may be present on both the top lid and the bottom of the packaging element.

In one embodiment, the holes of two adjacent packaging elements are aligned so that a hole on the top lid of one packaging element is connected to a hole on the bottom of the other packaging element stacked immediately above it to form a channel for gaseous communication directly between the two packaging elements. In some embodiments, the holes of either the top portion or the bottom portion of the individual packaging element are insertable holes that are surrounded by a wall protruding outwardly in a manner that such holes can be inserted into corresponding holes on the bottom of the individual packaging element stacked on its top, or the top of the individual packaging element stacked on its bottom, respectively, to create a channel for gaseous communication within the stacked packaging elements. In some embodiments, the wall of the holes comprises holes to facilitate gaseous flow to the inside of the packaging element.

The packaging elements are preferably designed so that they can be stacked together stably in a desirable number. For example, the top and bottom surface can be made sufficiently flat (except for the recessed and/or raised area). In some embodiments, the packaging element comprises a means for interlocking with another packaging element so as to increase stability of the stacked packaging elements. In one embodiment, the interlocking mechanism is the insertable holes described above. In another embodiment, the bottom of the packaging element may comprise a raised area corresponding to the recessed area of the lid of the packaging element stacked below it to form a locking mechanism between the raised area of said bottom and the recessed area of said lid. Preferably, the height of the raised area is less than the depth of the recessed area to allow a gap between the two packaging elements. In another embodiment, with reference to FIG. 6, the packaging element 600 comprises indentations 610 having a depth of Y′ on the sides of the bottom of the individual packaging element and protrusions 620 on the same sides of the top of the element with a height of X′, wherein the height X′ of the protrusion is greater than the depth Y′ of the indentation. As shown in FIG. 7, when two such packaging elements stacked together, the protruding sides of the top portion of the first packaging element 750 is interlocked with the indentations of the bottom of the second packaging element 700. A gap 770 is formed between the two packaging elements as the height X′ of the protrusions is greater than the depth Y′ of the indentations. The gap allows gaseous communication between the packaging elements and through the holes on the top and/or bottom surface of the packaging elements.

In still another embodiment, the packaging element may comprise one or more latches that can lock it with the packaging element stacked below and/or above it.

Alternatively, the stacked packaging elements can be stabilized by external means, such as being wrapped with ropes, covers, or confined with walls or other structures in the packaging system.

In a preferred embodiment, each individual packaging element is capable of withstanding the total weight of the other individual packaging elements stacked on its top. In one embodiment, the individual packaging element is capable of withstanding a minimum load of 150 kilograms over its surface. In one embodiment, the individual packaging element is capable of withstanding a minimum load of 350 pounds over its surface. In some embodiments, the surface area is about 200 to 400 square inches. In some embodiments, the surface area is about 1,200 to 2,600 square centimeters.

In one embodiment, the individual packaging elements are the same and are interchangeable. In one embodiment, the individual packaging elements are configured in different types. In one embodiment, the individual packaging elements are in different sizes. One type of packaging elements are to be placed on the bottom of the stack, which have perforations, channels, grooves, or holes on the top but do not have perforations, channels, grooves, or holes on the bottom. In some embodiments, a packaging element of this type comprises a docking means for connecting to an oxygen controller. The docking means may be a perforation, channel, groove, hole, protrusion or an inlet that can be connected to the oxygen controller and enable gaseous communication of the inside atmosphere of the packaging element with the oxygen controller when there is need to reduce or increase the content of oxygen inside the packaging element. The docking means can be sealed after the oxygen content of the packaging element(s) reaches a desired level and packaging element is disconnected from the oxygen controller.

A second type of packaging elements are to be placed in the middle of the stack, which have perforations, channels, grooves, or holes on both the bottom and the top.

A third type of packaging elements are to be placed on the top of the stack, which do not have perforations, channels, grooves, holes on the top but have perforations, channels, grooves, or holes on the bottom. In still another embodiment, there is provided a fourth type of packaging elements to be place on the top of the stack, which have perforations, channels, grooves, holes on both the bottom and the top, wherein the perforations, channels, grooves, holes on the top of said type of packaging elements are in gaseous communication directly with the means for controlling oxygen content.

In one embodiment, the individual packaging elements are color coded for easy identification of their content. In one embodiment, the individual packaging elements comprise a label or a bar code for identification.

In one embodiment, the individual packaging element comprises a thermally insulative material that is impermeable to gas. In another embodiment, the individual packaging element is a Styrofoam™ box which can be maintained at an adequate temperature necessary for the contents of the box.

Oxygen controlling means for controlling oxygen content including oxygen removal means and oxygen introduction means. Oxygen removal means includes, but is not limited to, gas flushing with an inert gas, such as nitrogen, carbon dioxide, intermittent or with vacuum/flush cycling over time, external oxygen scavengers that are in gaseous communication with the packaging system, or by using internal oxygen scavengers that are internal to the packaging system, or combinations thereof. Oxygen scavengers include, but are not limited to, fuel cells, pressure swing adsorption (PSA) and membrane separation methods, electrochemical devices, nitrogen membranes that filter oxygen out or other similar means, catalysts such as those utilizing elemental metal, such as platinum or palladium catalysts, oxygen absorbers include iron containing absorbers and oxygen adsorbers, etc. that are known in the art. Two or more of oxygen removal means can be combined. Oxygen introduction means includes but is not limited to flushing with a gas comprises oxygen, such as air or concentrated oxygen gas, or an opening allowing air to enter the packaging element or packaging system.

Methods

In one aspect, this disclosure provides a method for storing and transporting food in a controlled atmosphere in a unitized packaging system comprising a plurality of individual packaging elements, said method comprising:

-   -   a) placing food in two or more individual packaging elements,         wherein each said element comprises:         -   a bottom element;         -   side walls;         -   a closable top element; and         -   a means for gaseous communication with another individual             packaging element and/or with the gaseous environment of the             unitized packaging system;             -   wherein said individual packaging element comprises a                 thermally insulative material;     -   b) stacking the individual packaging elements, wherein a second         individual packaging element is stacked on a first individual         packaging element;     -   c) placing the individual packaging elements in a unitized         packaging system;     -   d) controlling oxygen content of the unitized packaging system;     -   e) closing the unitized packaging system so as to keep food in a         controlled atmosphere; and     -   f) optionally maintaining ambient pressure within the unitized         packaging system using a means for maintaining pressure.

In one embodiment, step d) further comprises using oxygen removing means, such as gas flushing, or oxygen scavengers. In another embodiment, step d) further comprises introducing a gas, other than air or oxygen, into the unitized packaging system. In a further embodiment, the gas is nitrogen and/or carbon dioxide. In another embodiment, the method further comprises controlling the temperature of the unitized packaging system. In some embodiments, the temperature is controlled at between about 20° C. and about −20° C., or between about 10° C. and about −5° C. (e.g., −1° C. or −2° C.), or between about 5° C. and about 0° C.

In one embodiment, the unitized packaging system is flushed with a gas, such as an inert gas, for example, nitrogen, carbon dioxide, or the like. The gas optionally comprises carbon monoxide. After the unitized packaging system reaches its destination, the individual packaging element(s) are removed from the unitized packaging system. Optionally, the unitized packaging system is flushed again with the gas before the individual packaging element(s) are removed from the modified or controlled atmosphere. The perforations, channels, grooves, holes of the packaging element can be sealed to minimize thermal losses as well as exposure to oxygen/air. The sealing can be conducted by applying foam, foil, an additional cover without any holes, a tape, etc. to the cover the holes. For example, a standard packaging tape (e.g., of a width of about 1-2 inches) can be applied to the channels covering the holes. These packages can then be released to the traditional distribution chain with the same protections against thermal shocks as a standard sealed package of Styrofoam™ or other materials of construction.

Reduced oxygen levels inside the unitized packaging system can be achieved by a variety of oxygen removal means including, but not limited to, gas flushing with an inert gas, such as nitrogen, carbon dioxide, intermittent or with vacuum/flush cycling over time, by using external oxygen scavengers that are in gaseous communication with the environment surrounding the packaging elements, or by using internal oxygen scavengers that are internal to the environment surrounding the packaging. In some embodiments, the oxygen scavenger is in gaseous communication with the environment surrounding the packaging elements through a pump. Oxygen scavengers include, but are not limited to, fuel cells, pressure swing, electrochemical devices, nitrogen membranes that filter oxygen out or other similar means, catalysts, adsorbers, absorbers, etc. that are known in the art.

In one aspect, this disclosure provides a method for storing and transporting food in a controlled atmosphere in a unitized packaging system comprising a plurality of individual packaging elements, which method comprises:

-   -   a) placing food in two or more individual packaging elements,         wherein each said element comprises:         -   a bottom element;         -   side walls;         -   a closable top element; and         -   a means for gaseous communication with another individual             packaging element and/or with the gaseous environment of the             unitized packaging system;             -   wherein said element comprises a thermally insulative                 material;     -   b) stacking individual packaging elements, wherein a second         individual packaging element is stacked on a first individual         packaging element;     -   c) placing the individual packaging elements in a unitized         packaging system;     -   d) controlling oxygen content of the unitized packaging system;     -   e) closing the unitized packaging system so as to keep food in a         controlled atmosphere; and     -   f) optionally maintaining ambient pressure within the unitized         packaging system using a means for maintaining pressure.

The steps of the method need not be performed sequentially according to the sequence described above. They can be performed in a different sequence. Certain steps may be preformed simultaneously.

In one embodiment, the oxygen content is controlled by a means for controlling oxygen content, which can cease operation when the oxygen content reaches a certain level, such as a desired low oxygen content, such as no more than 5%, 1%, 0.1%, etc., and can resume operation when the oxygen content is out of the desired range, such as above a desired low oxygen content.

In another embodiment, the method further comprises

-   -   g) removing one or more individual packaging element(s) from the         unitized packaging system;     -   h) covering the means for gaseous communication on the         individual packaging element; and     -   i) releasing the individual packaging element to a destination.

Steps a) to i) of the method need not be performed sequentially according to the sequence described above. They can be performed in a different sequence. Certain steps may be preformed simultaneously.

In still another embodiment, the method further comprises introducing an gas comprising oxygen to the packaging element or the packaging system to aid blooming of a food susceptible to blooming, such as a food comprising hemoglobin and/or myoglobin. For example, when a packaging element comprising a red meat product reaches a retail store, such a packaging element can be flushed with oxygen or air to aid the red meat to regain its red color (bloom).

In one embodiment, the individual packaging element comprises the thermally insulative material that is impermeable to gas. In another embodiment, the means for gaseous communication comprises perforations, channels, grooves, holes, or the like. 

1. A unitized packaging system for storing and/or transporting food under controlled temperature and atmosphere conditions which system comprises: two or more individual sealable packaging elements; an oxygen controlling means for controlling the oxygen content of the gaseous environment within the packaging system; and optionally a means for maintaining ambient pressure within the packaging system; wherein each of the individual packaging elements is in gaseous communication with at least another individual packaging element and with said oxygen controlling means; wherein said elements comprise a thermally insulative and gas impermeable material; and further wherein said elements are stackable with each other.
 2. A unitized packaging system for storing and/or transporting food in a controlled temperature and atmosphere which system comprises: two or more individual sealable packaging elements; and a means for gaseous communication between or among the individual packaging elements and/or throughout the unitized packaging system; wherein each said individual packaging elements comprises a thermally insulative and gas impermeable material; further wherein said individual packaging element can be stably stacked with each other, an oxygen controlling means for controlling oxygen content of the package system; and optionally a means for maintaining ambient pressure within the package system.
 3. The unitized packaging system of claim 1, wherein the individual packaging element comprises a closable top portion detachably connected to the side walls of the individual packaging element.
 4. The unitized packaging system of claim 1, wherein the thermally insulative material comprises a polymer.
 5. The unitized packaging system of claim 1, wherein the thermally insulative material is selected from the group consisting of polystyrene, polyester, polyethylene, polypropylene polyurethane, corn- or soy-based thermoset plastics or foam, and soy-based polyurethane.
 6. The unitized packaging system of claim 1, wherein the thermally insulative material comprises Styrofoam™.
 7. An individual packaging element suitable for use in a unitized packaging system for storing and transporting food in a controlled atmosphere comprising: a bottom portion; side walls; a closable top portion; and a means for gaseous communication with another individual packaging element and/or with the gaseous environment of the unitized packaging system, wherein the unitized packaging system comprises an oxygen controlling means for controlling oxygen content and optionally a means for maintaining ambient pressure; wherein said packaging element comprises a thermally insulative material, and the packaging element is capable of being stably stacked with another packaging element.
 8. The individual packaging element of claim 7, wherein the individual packaging element is capable of stably interlocking with another individual packaging element.
 9. A method for storing and transporting food in a controlled atmosphere in a unitized packaging system comprising a plurality of individual packaging elements, which method comprises: a) placing food in an individual packaging element, wherein said element comprises: a bottom element; side walls; a closable top element; and a means for gaseous communication with another individual packaging element and/or with the gaseous environment of the unitized packaging system; wherein said element comprises a thermally insulative material; b) stacking individual packaging elements, wherein a second individual packaging element is stacked on a first individual packaging element; c) placing the individual packaging elements in a unitized packaging system; d) controlling oxygen content of the unitized packaging system; e) closing the unitized packaging system so as to keep the food in a controlled atmosphere; and f) optionally maintaining ambient pressure within the unitized packaging system using a means for maintaining pressure.
 10. The method of claim 9, wherein step d) comprises using an inert gas flushing, or using oxygen scavengers.
 11. The method of claim 10, wherein step d) comprises introducing a gas, other than air or oxygen, into the unitized packaging system.
 12. The method of claim 11, wherein the gas is nitrogen and/or carbon dioxide.
 13. The method of claim 11, wherein the gas comprises carbon monoxide.
 14. The method of claim 9, wherein the method further comprises controlling temperature of the unitized packaging system.
 15. The method of claim 9, wherein the method further comprises: g) removing at least one individual packaging element from the unitized packaging system; h) covering the means for gaseous communication on the individual packaging element; and i) releasing the individual packaging element to a destination.
 16. The method of claim 9, wherein the method further comprises: j) introducing oxygen to the individual packaging element to enhance blooming of the food when the food is susceptible to blooming.
 17. The method of claim 9, wherein the controlling oxygen content of the unitized packaging system is reducing the oxygen content to below ambient concentration.
 18. The method of claim 9, wherein the controlling oxygen content of the unitized packaging system is introducing oxygen to the unitized packaging system when the unitized packaging system comprises a reduced oxygen content. 